I built a Chinese keyboard that shows English glosses as you type

Hi Product Hunt! I recently launched Danmu Bilingual Keyboard on the China App Store.

The idea is simple: when typing Chinese with Pinyin, English glosses appear alongside the Chinese candidates, so you can pick up vocabulary without switching to a dictionary.

The keyboard works offline for Pinyin input and glosses, and keeps its learning data on-device. It doesn’t require Full Access. The companion app includes a vocabulary notebook with manual editing and JSON import/export.

A little about the build: I brought a platform-independent Rust input core into an iOS Keyboard Extension, then built the surrounding app in Swift/UIKit. The extension has strict system boundaries, so keeping input and learning local became an important part of the design.

The main app includes AdMob ads and Firebase analytics/crash reporting; the keyboard extension itself contains neither SDK.

It’s currently available on the China App Store: https://apps.apple.com/cn/app/%E4%B8%B9%E6%9C%A8%E5%8F%8C%E8%AF%AD%E8%BE%93%E5%85%A5%E6%B3%95/id6820918304

I’d love feedback from people who use Chinese Pinyin keyboards or are learning English: do inline glosses feel useful while typing, or would you prefer a different way to save words?